1. Field of the Invention
The present invention relates to a detector for use in an X-ray imaging device, or the like.
2. Related Background Art
A conventional detector which can be used in an X-ray imaging device is described in the following references:
(1) Japanese Patent Laid-open No. (Hei)4-254377
This reference discloses an installation structure for an optical detector. In this installation structure, a back-illuminated photodiode array is connected via a pump to a signal processing section. Since the optical signal sampling electrodes are provided on the back face of the photoreceptor substrate, it is possible to use virtually all of the surface of the substrate as a light receiving face, and hence the aperture ratio is improved greatly compared to a conventional device. Moreover, the photoreceptor section uses a PIN type photodiode, the light incident via the I layer is absorbed with high efficiency, the junction capacitance can be reduced due to presence of the I layer, the depletion layer travel time of the carrier can be shortened by applying a high voltage, and the mechanical strength can be increased. The signal charge extracted from each pixel is input to a signal processing circuit substrate.
(2) Japanese Patent Laid-open No. (Hei)9-288184
This reference discloses a radiation detection device which adopts a layered structure for the light detecting section, wiring substrate, drive integrated circuit and signal processing integrated circuit, in order to protect the integrated circuits from radiation.
(3) Japanese Patent Laid-open No. (Hei)7-333348
This reference discloses an X-ray CT (Computer Tomography) device. Since the X-ray CT device emits the output of a photodiode array via a pump formed on the opposite side to the side on which the X-rays are incident, it permits the respective radiation detector elements to be arranged in a highly dense fashion in the two-dimensional direction, without reducing the detection sensitivity of the radiation detector elements, and therefore allows a broad range of X-ray data to be obtained in a single X-ray irradiation operation.
(4) Japanese Patent Laid-open No. (Hei)5-90554
This reference discloses a detector wherein the output of an HgCdTe photodiode array is connected via a pump in order to be read by an Si-CCD. The drive voltage from the DC power source driving the photodiode array is applied via the wiring on the Si-CCD. In other words, the surface on the Si-CCD side is formed with a dual wiring structure, a first wiring system being used to supply the output of the respective photodiodes to respective pixels (read-out regions) of the CCD via a pump, and the second wiring system forming wiring for supplying a voltage from the DC power source to a photodiode array.